One thought not mentioned so far and one I have experienced is check you do not have a small drip leak inside caravan as this can also lead to drop in preassure. this happened to me at start of this year and looked like a connection had slackened off and hose started dripping not enough to notice at first but being left and just turning off pump could have caused a very expensive repair to water ingress into floor walls etc. Luckilly when I noticed a damp patch under fridge at front ~(which at first I just thought was a spill or even melting ice) and on closer investigation eventuall founf drip under seating just next to water inlet but even in daylight was not easy to pinpoint. so my advice is instead of just turning off pump
check for leaks first and foremost
then check each tap individually and also check washer or 'O' ring on pum as this can also cause pump to run if perrished.